Weaning from veno-arterial extra-corporeal membrane oxygenation: which strategy to use?

Abstract

Significant advances in extracorporeal technology have led to the more widespread use of veno-arterial extracorporeal membrane oxygenation (VA ECMO) for cardiac failure. After a few days of mechanical assistance, the device can sometimes be successfully removed if the patient has partially or fully recovered from the condition that required the use of ECMO. However, procedures for weaning from VA ECMO are not standardized. The percentage of patients with refractory cardiogenic shock who are successfully weaned from ECMO varies from 31% to 76%. The high death rate after successful weaning shows that many questions remain unresolved in this field. In this review, we will discuss the various factors influencing survival and a successful weaning from VA ECMO, in addition to weaning approaches proposed in the literature. Based on this information, we will propose a strategy to optimize the weaning process. It is especially important that the VA ECMO is not removed while the patient is still recovering from the conditions that necessitated the use of VA ECMO implantation. First, damaged organs need to recover before attempting weaning and the patient should be considered hemodynamically stable. Secondly, the etiology of cardio-circulatory dysfunction must be compatible with myocardial recovery. Finally, weaning trials using echocardiographic and hemodynamic assessments are indispensable to assess the behavior of the ventricles during increases in preload and to determine whether the VA ECMO can be safely removed.